The slide on my used P22 is damaged. I can't get good enough pics of the damage so I'll do the best I can in describing it...

The damage runs along the bottom surface of the slide (the surface that "mates" with the frame, on both sides, there are some factory relief cuts at the point where the damage begins. It looks like someone has "whittled" away some of the metal with a small knife(?). The damage is irregular, that is, it is not smooth along the entire length, it truly looks whittled, nor is the effect symmetrical side to side. The damage is located about in the middle of the length of the slide, and is about 1.25-1.5" long. I cannot for the life of me find anything that might be causing it, there doesn't seem to be any other part of the firearm that could contact that part of the slide. I have painted the area to see if the paint will be scratched off at the next trip to the range, I would like to see if the damage is progressing or not. There is no damage to the actual slideways, nor is there any apparent damage anywhere else on this gun. The gun seems to function normally in all respects (1000 rnds), although there does seem to be some metallic crap in the debris that is removed during cleaning, but I cannot determine the origin or composition of this. I will say that the debris does not feel like shavings, which is what I would expect if it was from whittling, it feels more like very small grains of sand.

Also, I have noticed that the movement of the slide is slightly impeded by the hammer bob when racking the slide(no ammo or mag). The hammer doesn't cock back low enough to clear the slide, however, if I manually pull the hammer down a little more, the slide clears the hammer. Is this normal?

This is the only Walther I have ever owned/handled/shot so please try not to beat me up too bad if I'm being ignorant.

Thanks in advance,
Tim

Check out the tagged thread in the Walther Forum.

Those relief cuts in the slide actuate the disconnector ears on the trigger bar, which stick up on each side of the frame and "move" when you move the trigger.   They need to be rounded with a dremmel on the front.  

Send S&W / Walther  USA a nasty letter with photographs and they may send you a new slide.

But the "whittling" away is the sharp steel edges of the disconnector ears cutting into the soft zinc of the slide.